CRYPTIC CROSSWORD No. 16,110

ACROSS:

1 Invasion, 5 Pen pal, 9 Simplify, 10 Pogrom, 12 Rite, 13 Midshipman, 15 Nuclear winter, 19 Outboard motor, 23 Triple jump, 25 Afro, 28 Icecap, 29 Et cetera, 30 Esteem, 31 Acronyms.

DOWN:

1 Insure, 2 Vomit, 3 Silk, 4 Offside, 6 E coli, 7 Perimeter, 8 Luminary, 11 Tsar, 14 Echo, 15 Nutriment, 16 Add, 17 Into, 18 Contrite, 20 Raja, 21 Mimetic, 22 Morass, 24 Leave, 26 Fiery, 27 Veto.